Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind. This is the first and great commandment. And the second is like unto it, Thou shalt love thy neighbor as thyself. On these two commandments hang all the law and the prophets.

The books of the Old Testament, especially the books of Exodus and Leviticus, are full of rules and regulations. Following all of them, especially in this modern world, is next to impossible. And the various Church denominations have [or have had] their own lists of Thou shalts and Thou shalt nots. Some of these even seem to contradict each other. How can we sort through all this and decide what we should or should not do?

The two great commandments identified by Jesus form our guide, our touchstone, to determine what other commandments or rules we especially should pay attention to, and even identify some that we can ignore. Do they depend on or derive from the two Great Commandments? If they do, then we should follow them. If they don’t then they are rules, not commandments, and we should consider whether or not they are mandatory for us.

Obviously “Thou shalt not kill” and “Thou shalt not steal” qualify as deriving from “love thy neighbor as thyself”, as does the admonition in Leviticus which reads “You shall treat the stranger who sojourns with you as the native among you, and you shall love him as yourself” But what about the biblical prohibition against eating shellfish or pork, or the laws concerning animal sacrifice? There is no way we can derive either of these from the two Great Commandments. These should be considered as laws or rules for a certain people at a certain time for the purpose of learning discipline. They set the ancient Israelites apart from the people around them, to mark them out as God’s Chosen People. They were not meant to be universal laws. Similarly those who enter a monastic order take upon themselves adherence to a set of disciplines or rules peculiar to that particular monastic order, such as when to engage in communal prayer or even which psalms to recite at a particular time.

However, there is a link between these rules of discipline and the two great commandments. If we are to live together in harmony with our brothers and sisters it is best to have a set of rules, laws, and rituals in common that all of us agree to. The details don’t matter as long as we are in agreement.